The next rock is a porphyritic horn-stone, and splintery horn-stone. The most common substance imbedded in the former of these, is a white or grayish, or greenish granular limestone. It also contains rounded masses of flinty slate. On the surface it is often cellular, the limestone in its decomposition having dropped, or been washed out. The masses of limestone vary in dimensions from an inch to several feet square.
January 20th.– Arrived at the new settlement of Singapore. The selection of this island, for the purpose of a commercial settlement, has been extremely happy. It is placed in the direct route from Bengal towards China, and the numerous islands in the eastern part of the Archipelago. It is from its situation calculated to become the centre of the trade carried on in the China Seas and neighbouring countries, the kingdoms of Cochin China, Siam, &c., as well as of that of the Malayan Peninsula, and the western parts of India. It affords a safe and convenient anchorage at all seasons of the year; while from its insular situation, and being surrounded on every hand by innumerable islands, it is alike exempted from the destructive typhoons so common in the China Seas, and the scarce less furious tempests that occur on the coasts of India. Here indeed the atmosphere throughout the whole circuit of the year is serene and placid, to a degree unknown perhaps in any other part of our globe. The smooth expanse of the seas is scarcely ruffled by the wind. We seem, as it were, to be coasting along the banks of a lake. Storms are here felt as it were by reflection. The commotion excited in the China Seas by the tempest, is propagated to this distance, where it is seen to give a peculiar direction and increased velocity to the tides, and even occasions a considerable swell. A similar but less remarkable effect is produced by a tempest in the Bay of Bengal. Subject to the opposite impulses derived from these extensive seas, the tides amongst the islands become extremely irregular. At times they are found to run in one direction for several days successively, with the effect, in embayed places, of raising the water to a considerable height. In the numerous narrow channels which divide the lesser islands, this tide runs with very great rapidity, resembling water issuing through a sluice. The regular and periodical influence of the monsoons is but little, if at all, felt in these islands, the winds partaking more of the nature of what have been called sea and land breezes. Hence proceeds that uniformity of temperature which prevails in the atmosphere throughout the year. Hence also proceeds the more frequent fall of showers, and the absence of a proper, continued, and periodical rainy season. Few days elapse without the occurrence of showers, which thus produce the most agreeable effect in reducing the temperature and cherishing vegetation. Without the continued influence of moisture, these regions would certainly exhibit a far less cheerful picture, and the climate prove much less congenial to the human frame. Heat in the equatorial regions is thus benignly attempered to the constitution of man. It will be found to prove infinitely less pernicious to his system than it does some distance beyond the tropics, particularly in dry and arid climates. It is thus that the hot and dry winds of Upper India, to the extent of more than ten degrees beyond the tropic, exert such powerful and destructive influence on organized beings, and more particularly on the human frame. Its effects are too well known to require description. Inanimate life is not merely at a stand; it is threatened with total destruction, and with difficulty preserves a scanty gleam of future existence. Animated beings retire to the thickest shades, and even there pant for existence. The loose frame and acclimated constitution of the native inhabitant, is not proof against its baneful influence. What then must be its influence on constitutions so highly susceptible of excitement as that of the inhabitant of the North of Europe? The fatality amongst European troops has given too ample testimony. The physiologist, who has not witnessed the effect of high temperature on the human system, will with difficulty believe it capable of extinguishing life, often within the period of a single hour from the commencement of excitement. Its effects are no less rapid than fearful to the spectator; the mind in such cases partaking of the general excitement in a degree amounting even to complete mania. Within the tropics such effects are of rare occurrence.
The sandy shores of the ocean, offering a surface highly favourable for the developement of heat by reflection, will often be found of high and oppressive temperature during the day. Yet the temperature during the night is even here agreeable. Moderation, in point of temperature, is further attested by its benign effects on vegetable nature, which obtains a degree of developement unknown, perhaps, in any other part of the globe. We see trees encroaching even on the domain of the sea, their roots and branches covered with marine shells, as oysters, &c. The bare rocks, the stems of the smoothest trees, the most scanty portions of soil, are covered with an endless variety of plants. In point of adaptation, we observe situations equally favourable, and generally much more so, for the production of plants in most other parts of the globe. The single circumstance of a peculiarly modified temperature, would alone appear to be wanting. We are often at a loss to discover in what manner many of these vegetables derive nourishment, under circumstances, to appearance, so unfavourable. Moisture alone would seem to many to be their sole source of aliment; the elements of water being separated and assimilated by the organs of the plant. The quantity of simple moisture, or rather of apparently pure water, which some plants raise from the earth, is uncommonly great. This is beautifully exemplified in the organization of some creeping plants, in which the moisture is frequently conveyed the distance of forty, fifty, or a hundred yards, before it reaches the leaves, or fruit, or perhaps the assimilating organs of the vegetable. I have seen a plant of this sort, that had been accidentally cut across, continue to pour out pure, limpid, and tasteless water, in such quantity as to fill a wine glass in about half an hour. The stem and bark of this plant were quite green; there was no vestige of leaves, and it appeared that the water was proceeding unchanged to the extreme branches of the plant, in order to be assimilated. To other plants, even moisture, at least in any obvious quantity, does not seem to be indispensable. These are to be seen on bare rocks, without any ascertainable source of nutriment. They probably derive it from the air itself, or perhaps they decompose atmospheric air, and assimilate its elements.
This effect of equable though high temperature is not confined to the varied forms of vegetable life. The lower orders of animal existence attest its power no less strongly. The earth, the air, and the ocean, teem with life. Myriads of insects succeed to each other, in their labours at every varying period of the day and night. Some are busied in removing dead animal matter; others prey upon the living; while, to the great majority, the vegetable world affords an inexhaustible source of nourishment. In the great ocean, we observe the economy of nature directed to a similar purpose, in the habits of innumerable Corals, Madrepores, and Molluscæ; here too, as in other departments of nature, we observe the dependence which is established between animals of more perfect organization, and those generally of the very simplest structure, the operations of the latter being exerted in eliciting from inorganic matter substances capable of maintaining the numerous tribes of the former class. It is in this point of view, that a Coral bank affords, perhaps, one of the most interesting spectacles in nature. We scarce know which most to admire, the great beauty and variety of their forms, the singularity and simplicity of their structure, or the magnitude of effect, produced by means apparently so inadequate. The analogy between them and plants is particularly impressive; nor can we overlook the circumstance, that they are destined to perform analogous operations.
Our residence at Singapore made us acquainted with several very curious productions of this sort, among them, a singular species of Alcyonium may be mentioned. It passes here, under the fanciful name of Neptunian Goblet. It is in fact of the shape of a goblet, and its substance is intermediate between that of a sponge and a madrepore. Its colour,